Causal Agent: 

Bacteria (Xanthomonas campestris pv. phaseoli)

Characteristic Symptoms:
Leaf symptoms start as water-soaked spots that enlarge, become flaccid and necrotic with lemon yellow border.
Lesions are found along leaf margins and interveinal areas of the leaves and as they enlarge and coalesce, plants have burn-like appearance. 
Spots on pods are dark red-brown, water-soaked, circular and slightly sunken.
Conditions for Disease Development:
Warm temperatures (28-32°C) and high relative humidity favour disease development.
The bacterium can be spread to other plants/fields by windblown rain, soil, and plant debris, contact between wet leaves, irrigation water, insects like whiteflies and leafminers, farm implements and humans. 
The bacterium can overwinter in seed and infested bean straw and can survive for long periods of time.
Management and Control:
Use pathogen-free seeds.
Crop rotation with non-host plant for at least two years to reduce the inoculum level in the soil.
Remove weeds, volunteer beans and plant debris that serve as alternate hosts for the bacterium.
Use resistant varieties, if available.
Preventive application of copper-based fungicides (e.g. Cupravit®, Super BlueⓇ, Vitigran blueⓇ, FunguranⓇ, KocideⓇ, Hydroxide superⓇ).

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